Question

The reaction CH2CH2 + H2 → CH3CH3 is an example of

Answer 1

Answer:

Addition reaction.

Explanation:

There are four possible type of reactions in an organic compound, generally.

a) substitution: where a group or atoms substitutes another group or atom. for example reaction of an alkyl halide with hydroxide ion to give alcohol, where hydroxide ion replaces a halide ion.

b) elimination: Where a group or atom get eliminated from a molecule. For example synthesis of an alkene from an alkyl halide by elimination of hydrogen and halogen.

c) rearrangement: Here there is no addition or substitution or elimination but the molecule undergoes some atomic rearrangements to give a stable form.

d) Addition : in this there is addition of a molecule on a double bond.

In the given example the alkene is undergoing addition reaction as hydrogen is being added on it to give saturated alkane molecule.

Answer 2

The choices can be found elsewhere and as follows:

(1) substitution
(2) esterification
(3) addition
(4) fermentation 

I believe the correct answer is option 3. The reaction CH2CH2 + H2 → CH3CH3 is an example of an addition reaction. It is a reaction where two or more molecules combine to form a larger one. Hope this answers the question.